Search results for "humus"
showing 10 items of 117 documents
Pb-210 isotope as a pollutant emission indicator= Izotop Pb-210 jako znacznik emisji zanieczyszczeń
2015
Abstract Passive biomonitoring using 210Pb was used in the paper to evaluate pollutant deposition. Well-developed epiphytic foliose lichens Hypogymnia physodes growing on spruce branches were used in the studies. The samples of mosses Pleurozium schreberi and soil (raw humus) were collected from the area around the tree from which the samples of lichens were collected. The studies have shown that it is possible to identify dust emission sources using a radioactive lead isotope (210Pb). The highest activity of 210Pb was observed in areas with increased deposition of other pollutants, such as Ni, Cd, Cu and Pb, which may indicate that 210Pb is one of the emission components
NMR Study of Kraft Pulp Mill Waste and Natural Humic Substances
1988
High field proton NMR spectroscopy in DMSO-d6 solution is applied for structural analysis of main high molecular fractions of natural humus and waste lignin from kraft pulp mill. The spectra are similar in great part. Main differences appear in p-disubstituted benzene proton and -CH2 -CO-proton signals which are absent in spectrum of waste lignin obviously due to chlorination. A new observation of 51 Hz 1:1:1 triplet in both spectra is discussed.
Vegetation, soils, and humus forms of Sardinian holm oak forests and approximated cross-harmonization of vegetation types, WRB Soil Groups and humus …
2018
Five plant communities, related to elevation above sea level and geological substrata, are recognized in the holm oak forests of Sardinia (Italy). These forests show a considerable inhomogeneous structure due to present day and past uses. Coppice management prevails, influencing the quantity and quality of organic horizons. Most frequent mineral soils are Cambisols, Leptosols, and Regosols. Regarding the humus forms, Moder and, with less extent, Amphi, are prevailing. Furthermore, the paper presents a synoptic table giving a rough picture of the relationships between vegetation types, WRB Soil Groups and humus forms in selected Mediterranean ecosystems.
Effects of pentachlorophenol in forest soil: a microcosm experiment for testing ecosystem responses to anthropogenic stress
1996
Changes in the structure and function of a soil decomposer community and growth of birch (Betula pendula) due to chemical contamination were studied in laboratory microcosms. Sodium pentachlorophenate (PCP) was added to the humus layer of a simulated forest soil at three nominal concentrations (0, 50 and 500 mg kg-1 dry mass). After two growing periods (48 weeks), there were more small soft-bodied mites, but less collembolans and microbial biomass, in the higher PCP concentration treatment than in the other treatments. Number of enchytraeids were significantly reduced and fungal-feeding nematodes became extinct in the soil with the higher PCP concentration. Soil respiration did not change d…
Humus in World Soils
1996
Publisher Summary This chapter discusses the soil humus and total organic carbon (OC) content. It reviews the results concerning the changes in soil organic matter (SOM) chemical nature regardless of the technical methods used. Information about C cycling and storage in soils is also given. Soil humus is characterized by its amounts and properties such as water retention capacity, aggregation and cementing agent, and the ability to absorb both nutrients and contaminants. The uncontrolled decrease in soil humus content affects soil water regime, aeration, fertility, and purifying capacity. The chapter focuses on the main soil types and the areas of the world where they are found, and conside…
Soil humic acids formation and characteristics in a xeric mollisol reforested with two tree species
2002
Publisher Summary The study discussed in this chapter examines the influence on humic acids (HAs) characteristics of different plant species—Pinus halepensis Miller and Cedrus atlantica (Endl) Carriere—used in the restoration of a Mollisol under xeric conditions. The area studied is in Sicily (Italy), and two stands were compared 40 years after planting. The differences among soil profile developments in the two stands were investigated by chemical and biochemical methods to understand the different levels at which the processes of pedogenesis acted in the study area. The chapter analyzes some chemical and spectroscopic characteristics of HAs, separated from two selected pedons. The results…
Horizontal distribution of copper, nickel and enchytraeid worms in polluted soil
1999
We studied the horizontal distribution of Cu, Ni and enchytraeid worms (Cognettia sphagnetorum, Vejdovsky, Oligochaeta, Enchytraeidae) in forest soil near a Cu–Ni smelter in SW Finland. Soil samples were taken from a polluted site (2 km from the smelter) and a reference area (8 km from the smelter). We used a hierarchical sampling design in the polluted area for studying possible scale-dependent variability in parameters measured, distance between the samples (different scales) being 5, 50 and 500 cm. Distribution of metals was moderately heterogeneous in the polluted soil; coefficient of variances (CV), 26% for Cu and 32% for Ni. Instead, distribution of enchytraeids in the area was highly…
Labile carbon alleviates wood ash effects on soil fauna
2008
The combined effects of wood ash, sucrose and oxalic acid on enchytraeid size and biomass, the abundance of microbial-feeding nematodes and pH were studied in a full three-factorial design in laboratory microcosms containing 30 g of Norway spruce forest humus. Wood ash treatment reduced enchytraeid size and abundance, but these effects were offset by sucrose without any change in pH or moisture. The positive effects of sucrose were partially counteracted by oxalic acid. Both carbon compounds increased the abundance of obligate microbial-feeding nematodes, indicating enhanced microbial production.
Surface Activity of Humic Substances Within Peat Profile
2012
Humic substances are able to reduce the surface tension of their solutions and thus can act as surface-active substances in natural environment and possibly also for industrial applications. The ability to influence the surface tension of humic substance solutions depends on their origin. The objective of this study is a comparison of the ability of humic substances from peat profile to influence the surface tension of their solutions and identification of the structural characteristics of peat humic acids, determining their surfactant properties. Humic acids isolated from peat demonstrated significant impact of the surface tension of their solutions – they act as weak surfactants. The surf…
Changes in soil organic matter and soil humic substances following the afforestation of former agricultural lands in the boreal-nemoral ecotone (Latv…
2019
Abstract Abandonment of agricultural land is a widespread process in Northern Europe, which is associated with changes in content and distribution of organic matter in soil, including C stocks. There is insufficient information on changes in soil organic matter properties during afforestation of these lands. The aim of the study was to determine and describe the influence of afforestation on organic carbon (CORG) content and properties of soil organic matter (SOM) in mineral topsoil in the boreo-nemoral ecotone in Latvia. We studied soils in 4 model territories that represented abandoned farmlands and territories where mixed or coniferous forests were established at different times on forme…